Lipocalin 2 is a member of the lipocalin family which encompass more than 25 members (including proteins like retinol binding protein, a1 microglobulin, b lactoglobulin, apolipoprotein D and odorant binding protein). The members of the lipocalin family are characterized by their ability to bind small lipophilic substances in their hydrophobic core, and thereby serve as transporters of substances.